1. The periodontal disease classification system of the American Academy of Periodontology- an update;Wiebe;J. Can. Dent. Assoc.,2000
2. Classification of periodontal diseases: the dilemma continues;Devi;N. Y. State Dent. J.,2009
3. A new classification scheme for periodontal and peri-implant diseases and conditions - introduction and key changes from the 1999 classification;Caton;J. Clin. Periodontol.,2018
4. Standards for reporting chronic periodontitis prevalence and severity in epidemiologic studies;Holtfreter;J. Clin. Periodontol.,2015
5. Treating chronic periodontitis: current status, challenges, and future directions;Shaddox;Clin. Cosmet. Invest. Dent.,2010